Authenticating method for short-distance radio devices and a short-distance radio device

ABSTRACT

The invention provides a method for making mutual authentication between short-distance radio devices automatically or after confirmation by users, and a short-distance radio device for realizing the method. In a condition where a plurality of radio devices exist, each of the radio devices comprising a data communicating unit for performing short-distance radio communication and an authenticating unit for performing authentication of the radio device, the authenticating unit performs mutual authentication between two radio devices automatically or after confirmation by users of the radio devices when the two radio devices come closer to each other to such an extent that coverage areas of radio waves generated by the radio devices overlap with each other.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an authenticating method forshort-distance radio devices and a short-distance radio device. Moreparticularly, the present invention relates to an authenticating methodfor short-distance radio devices, which include data communicating unitsbased on short-distance radio communication such as represented byBluetooth, and which have the function enabling the radio devices toauthenticate mutually with ease, as well as the short-distance radiodevice itself.

2. Description of the Related Art

In conventional general authentication procedures for portable radio(wireless) equipment, a system is made up of a base station and pluralpieces of portable equipment, and an inquiry is issued to the basestation from each piece of portable equipment for authenticationthereof. The authentication is performed by inputting data, such as theID number and the password, which have been set in advance, and checkingfor verification of the inputted data whether it is in match with datastored as a database or the like in the base station.

However, when data such as the ID number and the password is inputtedfor the authentication as described above, such data itself tends to bea longer string of symbols comprising characters and numerals in mixedfashion, and hence an operation for inputting the data has becometroublesome. Also, mutual authentication procedures, which are generalin radio communication, have a tendency to be used more and more in manyapplications in future. This causes another problem that the complicatedauthentication procedures make a user interface also complicated.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide amethod and a construction capable of easily performing mutualauthentication between short-distance radio devices, in particular,portable devices.

To achieve the above object, an authenticating method for short-distanceradio devices and a short-distance radio device according to the presentinvention are constituted as follows.

-   (1) An authenticating method for short-distance radio devices,    comprising the steps of preparing a condition where a plurality of    radio devices exist, each of the radio devices comprising a data    communicating unit for performing short-distance radio communication    and an authenticating unit for performing authentication of the    radio device; and performing mutual authentication between two radio    devices by the authenticating unit automatically or after    confirmation by users of the radio devices when the two radio    devices come closer to each other to such an extent that coverage    areas of radio waves generated by the two radio devices overlap with    each other.-   (2) In the authenticating method for short-distance radio devices of    (1), the step of performing the authentication by the authenticating    unit is performed in a state where a transmission output of the    radio device is reduced to shorten a communication distance of the    radio device.-   (3) In the authenticating method for short-distance radio devices of    (2), the transmission output is reduced only in a particular one of    the radio devices.-   (4) In the authenticating method for short-distance radio devices of    (2), the transmission output is reduced upon turning-on of an    authentication button provided on the radio device.-   (5) In the authenticating method for short-distance radio devices of    (1), the step of performing the authentication by the authenticating    unit is performed in a state where reception sensitivity of the    radio device is reduced to shorten a communication distance of the    radio device.-   (6) In the authenticating method for short-distance radio devices of    (5), the reception sensitivity is reduced only in a particular one    of the radio devices.-   (7) In the authenticating method for short-distance radio devices of    (5), the reception sensitivity is reduced upon turning-on of an    authentication button provided on the radio device.-   (8) In the authenticating method for short-distance radio devices of    (1), the radio device is a portable device.-   (9) A short-distance radio device comprising a data communicating    unit for performing short-distance radio communication and an    authenticating unit for performing authentication of the radio    device, the authenticating unit of the radio device performing, in a    condition where a plurality of radio devices exist, mutual    authentication between two radio devices automatically or after    confirmation by users of the radio devices when the two radio    devices come closer to each other to such an extent that coverage    areas of radio waves generated by the radio devices overlap with    each other.-   (10) In the short-distance radio device of (9), the authenticating    unit performs the authentication in a state where a transmission    output of the radio device is reduced to shorten a communication    distance of the radio device.-   (11) In the short-distance radio device of (10), the transmission    output is reduced only in a particular one of the radio devices.-   (12) In the short-distance radio device of (10), the transmission    output is reduced upon turning-on of an authentication button    provided on the radio device.-   (13) In the short-distance radio device of (9), the authenticating    unit performs the authentication in a state where reception    sensitivity of the radio device is reduced to shorten a    communication distance of the radio device.-   (14) In the short-distance radio device of (13), the reception    sensitivity is reduced only in a particular one of the radio    devices.-   (15) In the short-distance radio device of (13), the reception    sensitivity is reduced upon turning-on of an authentication button    provided on the radio device.-   (16) In the short-distance radio device of (9), the radio device is    a portable device.

Thus, in a condition where a plurality of short-distance radio devicesexist, particularly portable radio devices, each of the radio devicescomprising a data communicating unit for performing short-distance radiocommunication and an authenticating unit for performing authenticationof the radio device, the authenticating unit performs mutualauthentication between two radio devices automatically or afterconfirmation by users when coverage areas of radio waves generated bythe radio devices overlap with each other, that is, when the two radiodevices come close to each other within a predetermined distance. As aresult, an operation for inputting complex data, such as theauthentication number, is eliminated and the operability can be greatlyimproved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the configuration of a terminal deviceas a short-distance radio device according to a first embodiment of thepresent invention;

FIG. 2 is a flowchart showing the operation of the terminal device;

FIG. 3 is an explanatory view showing the coverage area of radio waveswhen the terminal device is operated in the data communicating mode;

FIG. 4 is an explanatory view showing the coverage area of radio waveswhen the terminal device is operated in the authentication mode;

FIG. 5 is an explanatory view showing mutual authentication between theterminal devices operated in the authentication mode;

FIG. 6 is a block diagram showing the configuration of a terminal deviceas a short-distance radio device according to a second embodiment of thepresent invention;

FIG. 7 is a flowchart showing the operation of the terminal device ofFIG. 6;

FIGS. 8A, 8B and 8C are explanatory views showing an authenticationstate between the terminal devices of FIG. 6 operated in theauthentication mode with reduced reception sensitivity;

FIG. 9 is an explanatory view showing the coverage area of radio waveswhen the terminal device of FIG. 6 is operated in the data communicatingmode;

FIG. 10 is an explanatory view showing an authentication state betweenthe terminal devices of FIG. 6 when a particular terminal device isoperated in the authentication mode with reduced reception sensitivity;and

FIG. 11 is an explanatory view showing mutual authentication between theterminal devices of FIG. 6 operated in the authentication mode.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of an authenticating method for short-distance radio devicesand a short-distance radio device according to the present inventionwill be described below with reference to the drawings.

According to a first embodiment of the present invention, as shown inFIG. 1, the short-distance radio device for realizing the authenticatingmethod for short-distance radio devices is constituted by a portableterminal device such as a cellular phone. The terminal device comprisesa short-distance data communicating unit 110 which forms a datacommunicating means for performing short-distance radio communication;an authenticating unit 120 which serves as an authenticating meanscapable of decoding, for analysis to make authentication, data receivedby the short-distance data communicating unit 110 in the authenticationmode; an authentication button 130 for establishing the authenticationmode; and a radio output attenuating unit 140 for attenuating a radiooutput and narrowing the coverage area of radio waves, when theauthentication button 130 is depressed to turn on.

The operation of the terminal device thus constructed will be describedbelow in connection with a flowchart shown in FIG. 2 while referring toFIG. 1.

When the authentication button 130 is turned off, the terminal device isin the data communication mode in which ordinary communication iscarried out (steps ST110, ST120 and ST130). More specifically, as shownin FIG. 3, a terminal device A is in the ordinary operating state andproduces a transmission output capable of covering a certain largedistance (area indicated by W1 in FIG. 3).

When the authentication button 130 is depressed to turn on, the terminaldevice is brought into the authentication mode in which the transmissionoutput is reduced and the coverage area of transmitted radio waves isconsiderably narrowed (steps ST110, ST140 and ST150). For example, thetransmission output is reduced to such an extent that two terminaldevices are not able to receive or transmit data unless they arepositioned close to each other. Then, when the coverage areas of radiowaves transmitted from the terminal devices come into an overlappedrelation, i.e., when the terminal devices are positioned close to eachother, mutual authentication is enabled to start (step ST160). Morespecifically, as shown in FIG. 4, by depressing the authenticationbutton 130 of the terminal device A to turn on, the terminal device A isbrought into the authentication mode. In this operating mode, thetransmission output is considerably reduced and the communicationdistance (area indicated by W2 in FIG. 4) is set to such a range thattwo terminal device are not able to communicate data unless theyapproach very close to each other. Simultaneously, the other terminaldevice B, also in which the authentication button 130 is depressed andthe communication distance is narrowed as indicated by W3, comes closerto the terminal device A for mutual authentication.

Then, as shown in FIG. 5, when both the terminal devices A and B comeclose to each other and enter within a distance capable of communicatingdata therebetween (as indicated by communication distances W4 and W5),the mutual authentication is performed between the terminal devicesautomatically or after confirmation by users.

While this embodiment is arranged to perform the mutual authenticationin the state where the transmission outputs of both the terminal devicesA and B are reduced, the present invention is not limited to such anarrangement. As a matter of course, the transmission output of only oneparticular terminal device may be reduced.

Thus, since the coverage area of radio waves outputted in theauthentication mode is narrowed to such an extent that two terminaldevices are able to receive data only when they are positioned close toeach other, it is possible to prevent the mutual authentication frombeing performed among a number of terminal devices, and to carry out themutual authentication essentially in a one-to-one relation.

Next, a second embodiment of an authenticating method for short-distanceradio devices and a short-distance radio device according to the presentinvention will be described below with reference to the drawings.

According to the second embodiment of the present invention, as shown inFIG. 6, the short-distance radio device for realizing the authenticatingmethod for short-distance radio devices is constituted by a portableterminal device, such as a cellular phone, similarly to the firstembodiment described above. The terminal device comprises ashort-distance data communicating unit 110 which forms a datacommunicating means for performing short-distance radio communication;an authenticating unit 120 which serves as an authenticating meanscapable of decoding, for analysis to make authentication, data receivedby the short-distance data communicating unit 110 in the authenticationmode; an authentication button 130 for establishing the authenticationmode; and a reception sensitivity attenuating unit 150 for reducingreception sensitivity and shortening the communication distance, whenthe authentication button 130 is depressed to turn on.

The operation of the terminal device thus constructed will be describedbelow in connection with a flowchart shown in FIG. 7 while referring toFIG. 6.

When the authentication button 130 is turned off, the terminal device isin the data communication mode in which ordinary communication iscarried out (steps ST210, ST220 and ST230). More specifically, as shownin FIG. 8A, a terminal device A is in the ordinary operating state andproduces a transmission output capable of covering a certain largedistance (area indicated by W6 in FIG. 8A).

When the authentication button 130 is depressed to turn on, the terminaldevice is brought into the authentication mode in which the receptionsensitivity is reduced and the communication distance is considerablyshortened (steps ST210, ST240 and ST250). For example, the receptionsensitivity is reduced to such an extent that two terminal devices arenot able to receive or transmit data unless they are positioned close toeach other. Then, when the coverage areas of radio waves transmittedfrom the terminal devices are overlapped with each other and theterminal devices come into within a distance capable of communicatingdata between them, i.e., when the terminal devices are positioned closeto each other, mutual authentication is enabled to start (step ST260).More specifically, as shown in FIG. 8B, by depressing the authenticationbutton 130 of the terminal device A to turn on, the terminal device A isbrought into the authentication mode. In this operating mode, thereception sensitivity is considerably reduced and the communicationdistance (area indicated by W7 in FIG. 8B) is set to such a range thattwo terminal device are not able to communicate data unless theyapproach very close to each other. Simultaneously, the other terminaldevice B, also in which the authentication button 130 is depressed andthe communication distance is narrowed as indicated by W8, comes closerto the terminal device A for mutual authentication.

Then, as shown in FIG. 8 c, when both the terminal devices A and B comeclose to each other and enter within a distance capable of communicatingdata therebetween (as indicated by communication distances W9 and W10),the mutual authentication is performed between the terminal devicesautomatically or after confirmation by users.

While this embodiment is arranged to perform the mutual authenticationin the state where the reception sensitivity of each of the terminaldevices A and B is reduced, the present invention is not limited to suchan arrangement. As a matter of course, the reception sensitivity of onlyone particular terminal device may be reduced.

FIGS. 9 to 11 show mutual authentication between the terminal devices ofFIG. 6 when a particular terminal device (A in this embodiment) isoperated with reduced reception sensitivity. First, as shown in FIG. 9,the terminal device A is in the ordinary operating state and produces atransmission output capable of covering a certain large distance (areaindicated by W11 in FIG. 9).

In the above condition, when the authentication button 130 of theterminal device A is depressed to turn on, the terminal device A isbrought into the authentication mode as shown in FIG. 10. In thisoperating mode, the reception sensitivity is considerably reduced andthe communication distance (coverage area indicated by W12 in FIG. 10)is reduced to such a range that two terminal device are not able tocommunicate data unless they approach very close to each other.

Subsequently, the other terminal device B having the ordinarycommunication distance (coverage area W13 in FIG. 10) comes closer tothe terminal device A. Then, as shown in FIG. 11, when the terminaldevice B having the communication distance W13 comes closer to theterminal device A having the reduced communication distance (narrowedcoverage area) W12 to such an extent that both the terminal devicesenter within a distance capable of communicating data therebetween, themutual authentication is performed between the terminal devicesautomatically or after confirmation by users.

Additionally, when the terminal devices A and B are positioned close toeach other, a coverage area W14 of another terminal device C is outsidethe coverage areas of the terminal devices A and B. The mutualauthentication between the terminal devices A and C is therefore notperformed.

Thus, since the coverage area of radio waves outputted in theauthentication mode is narrowed to such an extent that two terminaldevices are able to receive data only when they are positioned close toeach other, it is possible to prevent the mutual authentication frombeing performed among a number of terminal devices, and to carry out themutual authentication essentially in a one-to-one relation.

The mutual authentication is performed by reducing the transmissionoutput in the first embodiment and by reducing the reception sensitivityin the second embodiment. As a matter of course, however, the mutualauthentication may be performed between terminal devices which are eachequipped with both the functions.

With the authenticating method for short-distance radio devices and theshort-distance radio device according to the present invention, asdescribed hereinabove, the mutual authentication is performed betweentwo terminal devices automatically or after confirmation by users whenthe terminal devices are brought into the authentication mode and arepositioned close to each other. As a result, an operation for inputtingdata for authentication is no longer required, and hence the operabilityis improved. Further, the mutual authentication can be performed with noneed of special highly-equipped user interfaces.

1. An authenticating method for portable radio devices, comprising datacommunicating means for performing radio communication over a firstcoverage area and authenticating means for performing authentication ofsaid portable radio devices over a second coverage area, comprising thesteps of: switching coverage area of two or more of said portable radiodevices, prior to initiating authentication between the portable radiodevices, from the first coverage area to the second coverage area, thesecond coverage area being smaller than the first coverage area;bringing, prior to initiating authentication between the portable radiodevices, the two or more portable radio devices having the secondcoverage area to within a proximity of one another so that the coverageareas of the two or more portable radio devices overlap; initiatingmutual authentication by establishing communication between the two ormore portable radio devices based only on the bringing of the two ormore portable radio devices to within the proximity; and performingmutual authentication between the two or more portable radio devices bysaid authenticating means automatically when the coverage area of thetwo or more portable radio devices overlap.
 2. The authenticating methodfor the portable radio devices according to claim 1, wherein the step ofperforming the authentication by said authenticating means is performedin a state where a transmission output of said portable radio devices isreduced to shorten a communication distance of said portable radiodevices.
 3. The authenticating method for the portable radio devicesaccording to claim 2, wherein the transmission output is reduced uponturning-on an authentication button provided on said particular one ofsaid portable radio devices.
 4. The authenticating method for theportable radio devices according to claim 1, wherein the step ofperforming the authentication by said authenticating means is performedin a state where reception sensitivity of said portable radio devices isreduced to shorten a communication distance of said portable radiodevices.
 5. The authenticating method for the portable radio devicesaccording to claim 4, wherein the reception sensitivity is reduced uponturning-on an authentication button provided on said particular one ofsaid portable radio devices.
 6. An authenticating method for portableradio devices, comprising data communicating means for performing radiocommunication over a first coverage area and authenticating means forperforming authentication of said portable radio devices over a secondcoverage area, comprising the steps of: switching coverage area of aportable radio device, prior to initiating authentication between theportable radio devices, from the first coverage area to the secondcoverage area, the second coverage area being smaller than the firstcoverage area; bringing, prior to initiating authentication between theportable radio devices, the two or more portable radio devices havingthe second coverage area to within a proximity of one another so thatthe coverage areas of the two or more portable radio devices overlap;and performing mutual authentication between two or more portable radiodevices by said authenticating means automatically when the coveragearea of the two or more portable radio devices overlap, wherein atransmission output of only a particular one of said portable radiodevices is reduced to shorten a communication distance of said portableradio devices.
 7. An authenticating method for portable radio devices,comprising data communicating means for performing radio communicationover a first coverage area and authentication means for performingauthentication of said portable radio devices over a second coveragearea, comprising the steps of: switching coverage area of a portableradio device, prior to initiating authentication between the portableradio devices, from the first coverage area to the second coverage area,the second coverage area being smaller than the first coverage area;bringing, prior to initiating authentication between the portable radiodevices, the two or more portable radio devices having the secondcoverage area to within a proximity of one another so that the coverageareas of the two or more portable radio devices overlap; and performingmutual authentication between the two or more portable radio devices bysaid authenticating means automatically when the coverage area of thetwo or more portable radio devices overlap, wherein a receptionsensitivity of only a particular one of said portable radio devices isreduced to shorten a communication distance of said portable radiodevices.
 8. A portable radio device comprising: data communicating meansfor performing radio communication over a first coverage areas;authenticating means for performing authentication over a secondcoverage area of said portable radio device; and switching means forswitching the coverage area of said portable radio device, prior toinitiating authentication between the portable radio devices, from saidfirst coverage area to said second coverage area, said second coveragearea being smaller than said first coverage area; wherein saidauthenticating means of said portable radio device initiates mutualauthentication between two or more portable radio devices based only onthe bringing of the two or more portable radio devices to within aproximity such that the coverage areas of the two or more portable radiodevices overlap; and wherein said authenticating means of said portableradio device performs mutual authentication between the two or moreportable radio devices automatically when the two or more portable radiodevices are brought in proximity to one another so that the secondcoverage areas overlap.
 9. The portable radio device according to claim8, wherein said authenticating means performs the authentication in astate where a transmission output of said plurality of portable radiodevices is reduced to shorten a communication distance of said portableradio devices.
 10. The portable radio device according to claim 9,wherein the transmission output is reduced upon turning-on anauthentication button provided on said particular one of said portableradio devices.
 11. The portable radio device according to claim 8,wherein said authenticating means performs the authentication in a statewhere reception sensitivity of said portable radio devices is reduced toshorten a communication distance of said portable radio devices.
 12. Theportable radio device according to claim 11, wherein the receptionsensitivity is reduced upon turning-on an authentication button providedon said particular one of said portable radio devices.
 13. A portableradio device comprising: data communicating means for performing radiocommunication over a first coverage area; authenticating means forperforming authentication over a second coverage area of said portableradio device; and switching means for switching the coverage area ofsaid portable radio device, prior to initiating authentication betweenthe portable radio devices, from said first coverage area to said secondcoverage area, said second coverage area being smaller than said firstcoverage area; wherein said authenticating means of said portable radiodevice performs, in a condition where a plurality of portable radiodevices exist, mutual authentication between two or more portable radiodevices automatically when the two or more portable radio devices arebrought in proximity to one another so that the second coverage areasoverlap, and wherein a transmission output of only a particular one ofsaid portable radio devices is reduced to shorten communication distanceof said portable radio devices.
 14. A portable radio device comprising:data communicating means for performing radio communication over a firstcoverage area; authenticating means for performing authentication over asecond coverage area of said portable radio device; and switching meansfor switching the coverage area of said portable radio device, prior toinitiating authentication between the portable radio devices, from saidfirst coverage area to said second coverage area, said second coveragearea being smaller than said first coverage area; wherein saidauthenticating means performs, in a condition where a plurality ofportable radio devices exist, mutual authentication between two or moreportable radio devices automatically when the two or more portable radiodevices are brought in proximity to one another so that the secondcoverage areas overlap, and wherein a reception sensitivity of only aparticular one of said portable radio devices is reduced to shortencommunication distance of said portable radio devices.
 15. Anauthenticating method for mobile radio devices, comprising the steps of:providing a plurality of mobile radio devices, each of said plurality ofmobile radio devices comprising data communicating means for performingradio communication and authenticating means for performingauthentication of said mobile radio devices; reducing, prior toinitiating authentication, the coverage areas of the mobile radiodevices; initiating mutual authentication by establishing communicationbetween two or more radio devices based only on the bringing of the twoor more radio devices to within a proximity such that the coverage areasof radio waves generated by the two or more mobile radio devicesoverlap; and performing mutual authentication between two or more mobileradio devices by said authenticating means automatically when the two ormore mobile radio devices come sufficiently closer to each other thatcoverage areas of radio waves generated by the two or more mobile radiodevices overlap.